Cassandra

When you configure the Cassandra destination, you define connection information and map
incoming fields to columns in the Cassandra table. You also configure whether the
destination writes each batch to Cassandra as a logged batch or an unlogged batch.

You configure whether the destination uses no authentication or username and password
authentication to access the Cassandra cluster. If you install the DataStax Enterprise
(DSE) Java driver, you can configure the destination to use DSE username and password
authentication or Kerberos authentication.

You can also enable SSL/TLS for the connection.

Batch Type

The Cassandra destination can write batches to a
Cassandra cluster using one of the following batch types:

Logged

Logged batches written to Cassandra use the Cassandra distributed batch log and
are atomic. This means that the destination can only write entire batches of
records to Cassandra. If an error occurs with one or more records in a batch,
the destination fails the entire batch. When a batch fails, all records are sent
to the stage for error handling.

Unlogged

Unlogged batches written to Cassandra do not use the Cassandra distributed batch
log and are nonatomic. This means that the destination can write partial
batches of records to Cassandra. If an error occurs with one or more records in
a batch, the destination sends only those failed records to the stage for error
handling. The destination writes the remaining records in the batch to
Cassandra.

Before selecting one of the DSE authentication providers, install the DSE Java driver version
1.2.4 or later. For a compatibility matrix, see the Cassandra documentation. For information about installing additional drivers, see
Install External Libraries.

Kerberos (DSE) Authentication

If you install the DSE Java driver, you can use
Kerberos authentication to connect to a Cassandra cluster. When you use Kerberos
authentication, Data Collector
uses the Kerberos principal and keytab to connect to the cluster. By default, Data Collector
uses the user account who started it to connect.

The Kerberos principal and keytab are defined in the Data Collector
configuration file, $SDC_CONF/sdc.properties. To use Kerberos
authentication, configure all Kerberos properties in the Data Collector
configuration file, install the DSE Java driver, and then enable Kerberos (DSE)
authentication in the Cassandra destination.

Cassandra Data Types

Due to
Cassandra requirements, the data types of the incoming fields must match the data types of the
corresponding Cassandra columns. When appropriate, use a Field Type Converter processor
earlier in the pipeline to convert data types.

For details about the conversion of Java data types to Cassandra data types, see the Cassandra
documentation.

The Cassandra destination supports the following Cassandra data types:

ASCII

Bigint

Boolean

Counter

Decimal

Double

Float

Int

List

Map

Text

Timestamp

Timeuuid

Uuid

Varchar

Varint

The following data types are not supported at this time:

Blob

Inet

Set

Configuring a Cassandra Destination

Configure a Cassandra
destination to write data to a Cassandra cluster.

In the Properties panel, on the General tab, configure the
following properties: